sdl-audio/main.c

#include <SDL2/SDL.h>
#include <SDL2/SDL_ttf.h>
#include <stdio.h>

#include "texture.h"
#include "audio.h"

const int SCREEN_WIDTH = 640;
const int SCREEN_HEIGHT = 480;

typedef enum {
	SELECTING_DEVICE,
	RECORDING,
	RECORDED,
	PLAYBACK,
} application_state;

typedef struct state {
	application_state application_state;
	audio_state audio;
	int device_index;
} state;

int init();
void destroy();
int select_device(SDL_KeyboardEvent* key_event, int max_index);

void application_state_to_string(application_state state, char* string);

SDL_Window* window = NULL;
SDL_Renderer* renderer = NULL;

int num_devices = 0;

int handle_input(SDL_Event* event, state* state);
void handle_task(state* state);
int main(int argc, char* argv[])
{
	if (!init()) return 1;

	num_devices = SDL_GetNumAudioDevices(1);
	printf("Num audio devices: %i\n", num_devices);
	char char_buffer[64];
	char default_fmt[] = "Device selected: %i";

	state state;
	state.application_state = SELECTING_DEVICE;
	audio_init(&state.audio);
	state.device_index = -1;

	text_texture display_text_texture;
	text_texture_init(&display_text_texture, renderer);
	sprintf(char_buffer, default_fmt, state.device_index);
	text_texture_load(&display_text_texture, char_buffer);

	text_texture device_textures[num_devices];
	for (int i = 0; i < num_devices; i++) {
		text_texture_init(&device_textures[i], renderer);
		sprintf(char_buffer, "%i: %s", i, SDL_GetAudioDeviceName(i, 1));
		text_texture_load(&device_textures[i], char_buffer);
	}

	text_texture state_text_texture;
	text_texture_init(&state_text_texture, renderer);
	application_state_to_string(state.application_state, char_buffer);
	text_texture_load(&state_text_texture, char_buffer);

	SDL_Event event;
	while (1) {
		while (SDL_PollEvent(&event)) {
			SDL_Keycode keysym = event.key.keysym.sym;
			switch (event.type) {

			case SDL_QUIT:
				goto cleanup;
				break;

			case SDL_KEYDOWN:
				if (!handle_input(&event, &state)) goto cleanup;
				break;

			}
		}

		handle_task(&state);

		sprintf(char_buffer, default_fmt, state.device_index);
		text_texture_load(&display_text_texture, char_buffer);
		application_state_to_string(state.application_state, char_buffer);
		text_texture_load(&state_text_texture, char_buffer);

		// Clear the screen
		SDL_SetRenderDrawColor(renderer, 0, 0, 0, 255);
		SDL_RenderClear(renderer);

		// Render
		text_texture_render(&display_text_texture, 0, 0);

		if (state.application_state == SELECTING_DEVICE) {
			int text_y_offset_step = display_text_texture.height * 2;
			int text_y_offset = text_y_offset_step;
			for (int i = 0; i < num_devices; i++) {
				text_texture_render(&device_textures[i], 0, text_y_offset);
				text_y_offset += text_y_offset_step;
			}
		}

		text_texture_render(&state_text_texture, 0, SCREEN_HEIGHT - state_text_texture.height);

		// Update the screen
		SDL_RenderPresent(renderer);
	}

cleanup:
	printf("Cleanup\n");
	audio_destroy(&state.audio);
	text_texture_free(&display_text_texture);
	for (int i = 0; i < num_devices; i++) {
		text_texture_free(&device_textures[i]);
	}
	destroy();

	return 0;
}

int handle_input(SDL_Event* event, state* state)
{
	SDL_Keycode keysym = event->key.keysym.sym;
	switch (state->application_state) {

	case SELECTING_DEVICE:
		switch (keysym) {
		case SDLK_y:
		case SDLK_RETURN:
			if (state->device_index == -1 || !state->audio.recording_device_id) break;
			SDL_LockAudioDevice(state->audio.recording_device_id);
			memset(state->audio.recording_buffer, 0, state->audio.recording_buffer_size);
			state->audio.recording_buffer_position = 0;
			SDL_UnlockAudioDevice(state->audio.recording_device_id);
			SDL_PauseAudioDevice(state->audio.recording_device_id, 0);
			state->application_state = RECORDING;
			break;
		case SDLK_q:
		case SDLK_ESCAPE:
			return 0;
			break;
		}
		int device_index_new = select_device(&event->key, num_devices);
		if (device_index_new == -1) break;
		if (device_index_new == state->device_index) break;
		state->device_index = device_index_new;
		SDL_CloseAudioDevice(state->audio.recording_device_id);
		audio_recording_init(&state->audio, state->device_index);

		break;

	case RECORDING:
		switch (keysym) {
		case SDLK_q:
		case SDLK_ESCAPE:
			SDL_PauseAudioDevice(state->audio.recording_device_id, 1);
			state->application_state = SELECTING_DEVICE;
			break;
		}
		break;

	case RECORDED:
		switch (keysym) {
		case SDLK_y:
		case SDLK_RETURN:
			if (!state->audio.playback_device_id)
				audio_playback_init(&state->audio);
			SDL_LockAudioDevice(state->audio.playback_device_id);
			state->audio.recording_buffer_position = 0;
			SDL_UnlockAudioDevice(state->audio.playback_device_id);
			SDL_PauseAudioDevice(state->audio.playback_device_id, 0);
			state->application_state = PLAYBACK;
			break;
		case SDLK_q:
		case SDLK_ESCAPE:
			state->application_state = SELECTING_DEVICE;
			break;
		}
		break;

	case PLAYBACK:
		switch (keysym) {
		case SDLK_q:
		case SDLK_ESCAPE:
			SDL_PauseAudioDevice(state->audio.playback_device_id, 1);
			state->application_state = RECORDED;
			break;
		}
		break;

	}
	return 1;
}

void handle_task(state* state)
{
	switch (state->application_state) {

	case SELECTING_DEVICE:
		break;

	case RECORDING:
		if (state->audio.recording_buffer_position >= state->audio.recording_buffer_size)
			state->application_state = RECORDED;
		break;

	case RECORDED:
		break;

	case PLAYBACK:
		if (state->audio.recording_buffer_position >= state->audio.recording_buffer_size)
			state->application_state = RECORDED;
		break;

	}
}

int init()
{
	if (SDL_Init(SDL_INIT_VIDEO | SDL_INIT_AUDIO) < 0) {
		printf("SDL could not initialize! SDL Error: %s\n", SDL_GetError());
		return 0;
	}

	if (TTF_Init() == -1) {
		printf("TTF could not initialize! TTF Error: %s\n", TTF_GetError());
		return 0;
	}

	window = SDL_CreateWindow("SDL record", SDL_WINDOWPOS_UNDEFINED,
	                          SDL_WINDOWPOS_UNDEFINED, SCREEN_WIDTH,
	                          SCREEN_HEIGHT, SDL_WINDOW_SHOWN);

	if (!window) {
		printf("Window could not be created! SDL Error: %s\n", SDL_GetError());
		return 0;
	}

	renderer = SDL_CreateRenderer(window, -1, SDL_RENDERER_ACCELERATED);
	if (!renderer) {
		printf("Renderer could not be created! SDL_Error: %s\n", SDL_GetError());
		return 0;
	}

	return 1;
}

void destroy()
{
	SDL_DestroyRenderer(renderer);
	SDL_DestroyWindow(window);
	TTF_Quit();
	SDL_Quit();
}

int select_device(SDL_KeyboardEvent* key_event, int max_index)
{
	SDL_Keycode keycode = key_event->keysym.sym;
	/*SDL_Keycode mod = key_event->keysym.mod;*/

	int keycode_is_num = (keycode >= SDLK_0 && keycode <= SDLK_9);
	/*int no_mod = (mod == 0);*/
	/*if (!keycode_is_num || !no_mod) {*/
	if (!keycode_is_num) {
		printf("Not number: %c <%u>\n", keycode, keycode);
		return -1;
	} else {
		printf("Is number: %c <%u>\n", keycode, keycode);
	}

	int index = keycode - SDLK_0;
	if (index >= max_index) return -1;

	return index;
}

void application_state_to_string(application_state state, char* string)
{
	switch (state) {
	case SELECTING_DEVICE:
		sprintf(string, "Selecting Device [0-9] -> [y/RET], ");
		break;
	case RECORDING:
		sprintf(string, "Recording [ESC] to cancel");
		break;
	case RECORDED:
		sprintf(string, "Recorded [y/RET] to play [ESC] to Select");
		break;
	case PLAYBACK:
		sprintf(string, "Playing");
		break;
	}
}